PAR-2 Agonist

ABSTRACT

The present invention relates to a pharmaceutical composition for preventing/treating conditions associated with PAR-2. The present invention also relates to a method for preventing/treating the condition using the pharmaceutical composition and use for manufacturing the pharmaceutical composition. The pharmaceutical composition comprises a compound represented by the following general formula (1), salt or solvate thereof and a pharmaceutically acceptable carrier: Ar—CO-AA 1 -AA 2 -AA 3 -AA 4 -NH—X—Y (1) wherein, Ar represents a phenyl group or an aromatic heterocyclic group optionally having substituent(s): AA 1  represents a hydrophobic amino acid: AA 2  represents an amino acid absent of substituent (s) having more than two carbon atoms: AA 3  represents an amino acid absent of substituent(s) having more than two carbon atoms: AA 4  represents a basic amino acid: X represents a straight-chain or branched bivalent saturated aliphatic hydrocarbon group having 1 to 6 carbon atoms: Y represents basic substituent (s); straight-chain, branched, or cyclic bivalent saturated aliphatic hydrocarbon group having 1 to 6 carbon atoms, or an aromatic hydrocarbon group having 6 to 10 carbon atoms. The compound represented by the general formula (1) has dramatically improved PAR-2 activation potency compared to peptide comprised of 6 amino acids (Tethered receptor agonist peptide: TRAP) in spite of reduction of the number of amino acid.

TECHNICAL FIELD

The present invention relates to PAR-2 agonist, and a pharmaceuticalcomposition containing the PAR-2 agonist as an active ingredient forpreventing/treating PAR-2 associated diseases, particularly the presentinvention relates to PAR-2 agonist useful for development of apharmaceutical preparation as well as prevention of development orprogress, amelioration, and treatment of conditions such as fever,dryness of eye, corneal epithelial detachment, keratitis, cornealulceration, conjunctival inflammation, dysfunction of masticatory,dysphagia, taste disorder, mouth odor, mouth discomfort, mouthinfection, mouth inflammation, cardiovascular functional disorder, acuterespiratory distress syndrome, peptic ulcer such as gastric ulcerationand duodenal ulcer, gastric inflammation, visceral pain, diarrhea,enteritis such as ulcerative colitis, kidney disorder such as nephritis,pancreatitis, ulcer tissue, bone resorption, dysmenorrhea, prematurelabor, nephrosis, or symptom of low blood pressure.

PAR (Protease-activated receptor)-2 is one of the protease-activatedreceptor (PAR) belonging to the G protein-coupled receptor family of7-times transmembrane type cloned in 1994 by Nystedt et al. (Proc. Natl.Acad. Sci. USA, 1994, 91, 9208-9212). PAR is a receptor familycharacterized by its activation occurred when a specific site ofamino-acid sequence of the N-terminus of the molecule is cleaved byserine protease such as thrombin or trypsin and a new N-terminalfragment bind to ligand binding site of the molecule itself. To date,four types of PARs: PAR-1, PAR-2, PAR-3 and PAR-4, have been cloned; andeach of PAR-1, PAR-3 and PAR-4 has been revealed its function asreceptor related to platelet aggregation induced by thrombin. PAR-2shares a number of similarities in structure and activation mechanismwith other PARs; however, functional differences between PAR-2 and otherPARs are suggested, for example, the PAR-2 is activated by trypsin ortryptase but not activated by thrombin.

PAR-2 is known to be activated by a tissue factor/factor VIIa, factorXa, acrosin (a type of sperm protease) and trypsin-like serine proteaseidentified in rat brain further to trypsin and tryptase(PharmacologicalRev. 53, 245-282, 2001, Br. J. Pharmacol. 1998, 123, 1434-1440), and itis reported that PAR-2 activation is useful in preventing and treatingreduced salivary secretion, reduced lacrimal secretion and alimentarydiseases (Japanese Patent Application Laid-open No. 2001-064203,Japanese Patent Application Laid-open No. 2001-181208, Japanese PatentApplication Laid-open No. 2001-233790, U.S. Pat. No. 5,888,529, and U.S.Pat. No. 5,958,407).

In biochemical experiments, the peptides mainly composed of 6 aminoacids, such as Ser-Leu-Ile-Gly-Lys-Val-OH, Ser-Leu-Ile-Gly-Lys-Val-NH₂,Ser-Leu-Ile-Gly-Arg-Leu-OH, or Ser-Leu-Ile-Gly-Arg-Leu-NH₂ having thesame sequence as Par-2 ligand (Tethered receptor agonist peptide:TRAP)are widely used as a PAR-2 activator; however, it is significant toobtain a compound having a simpler structure considering usefulness inthe development of pharmaceutical preparation. An example of lowmolecular PAR-2 agonists heretofore reported isN_(α)-benzoyl-Arg(NO₂)-Leu-NH₂, and intensity of this compound toactivate PAR-2 is about 1/100 of TRAP (Bioorg. Med. Chem. Lett. 2002,12, 21-24). A compound having acyl group such as 2-furoyl substitutedfor an amino acid at N-terminus of TRAP is reported as PAR-2 activatingagent (WO 03/104268); however, it is desired to obtain a compound havinga more simplified structure. A method for reducing the number of aminoacid composing the peptide is assumed as one of the methods to simplifythe structure of TRAP. A peptide composed of 5 to 7 amino acids isclaimed as PAR-2 activating agent in WO 96/23225-[(U.S. Pat. No.5,763,575, U.S. Pat. No. 5,874,400) COR Therapeutics Inc.], and for apeptide composed of 5 amino acids (AA¹-AA²-AA³-AA⁴-AA⁵), each amino acidis defined as AA¹: small amino acid or threonine, AA² and AA³:neutral/nonpolar/large/nonaromatic amino acid, AA⁴: small amino acid,AA⁵:basic amino acid. Even the amino acids are specified according toits property as above, simply reducing the number of 6 amino acidscomposing the peptide usually results in decreased PAR-2 activation(Pharmacol.Rev. 2001, 53, 245-282, J. Pharmacol. Exp. Ther. 1999, 290,753-760, Mol. Pharmacol. 1996. 49, 229-233). However, there areconsiderable difficulties in industrial production of peptides composedof 6 amino acids; therefore, it has been desired to develop shorteragonist peptides having equal or higher ability of activation.

DISCLOSURE OF INVENTION

Accordingly, the object of the present invention is to provide a PAR-2agonist retaining comparable ability to activate PAR-2 to that of TRAPor with the ability improved even with reducing the number of amino acidcomposing the peptide. That is, the object of the present invention isto provide a PAR-2 agonist useful for development of a pharmaceuticalpreparation as well as prevention of development or progress,amelioration, and treatment of conditions relating to PAR-2, such asfever, dryness of eye, corneal epithelial detachment, keratitis, cornealulceration, conjunctival inflammation, dysfunction of masticatory,dysphagia, taste disorder, mouth odor, mouth discomfort, mouthinfection, mouth inflammation, cardiovascular functional disorder, acuterespiratory distress syndrome, peptic ulcer such as gastric ulcerationand duodenal ulcer, gastric inflammation, visceral pain, diarrhea,enteritis such as ulcerative colitis, kidney disorder such as nephritis,pancreatitis, ulcer tissue, bone resorption, dysmenorrhea, prematurelabor, nephrosis, or symptom of low blood pressure.

In view of the circumstances described above, the present inventors madeextensive study, and as a result they found that a compound representedby the general formula (1):

[General formula 1]

A_(r)-CO-AA₁-AA₂-AA₃-AA₄-NH—X—Y  (1)

or salt thereof or solvate thereof have dramatically improved ability toactivate PAR-2 compared to TRAP with reducing the number of amino acidcomposing the peptide, and completed the present invention.

Within the general formula (1):

Ar represents a phenyl group or an aromatic heterocyclic groupoptionally having substituent(s);

AA₁ represents a hydrophobic amino acid;

AA₂ represents an amino acid absent of substituent(s) comprising morethan two carbon atoms;

AA₃ represents an amino acid absent of substituent(s) comprising morethan two carbon atoms;

AA₄ represents a hydrophobic amino acid;

X represents a bivalent saturated aliphatic hydrocarbon group having 1to 6 carbon atoms;

Y represents basic substituent(s); straight, branched, or cyclicbivalent saturated aliphatic hydrocarbon group having 1 to 6 carbonatoms, or aromatic hydrocarbon having 6 to 10 carbon atoms.

Accordingly, the present invention provides the compound represented bythe above-described general formula (1), salt thereof or solvatethereof.

The present invention also relates to a pharmaceutical compositioncomprising a compound represented by the general formula (1) of theabove, salt thereof, or solvate thereof, and pharmaceutically acceptablecarrier for preventing and/or treating conditions associated with PAR-2.

The present invention further relates to a pharmaceutical compositioncomprising a compound represented by the general formula (1) of theabove, salt thereof, or solvate thereof, and pharmaceutically acceptablecarrier for preventing/treating fever, dryness of eye, cornealepithelial detachment, keratitis, corneal ulceration, conjunctivalinflammation, dysfunction of masticatory, dysphagia, taste disorder,mouth odor, mouth discomfort, mouth infection, mouth inflammation,cardiovascular functional disorder, acute respiratory distress syndrome,peptic ulcer such as gastric ulceration and duodenal ulcer, gastricinflammation, visceral pain, diarrhea, enteritis such as ulcerativecolitis, kidney disorder such as nephritis, pancreatitis, ulcer tissue,bone resorption, dysmenorrhea, premature labor, nephrosis, or symptom oflow blood pressure.

The present invention further relates to a method forpreventing/treating conditions associated with PAR-2, comprisingadministrating an effective amount of a compound represented by thegeneral formula (1) of the above, salt thereof, or solvate thereof, andpharmaceutically acceptable carrier to a patient susceptible to orsuffering from a condition associated with PAR-2.

The present invention further relates to a method forpreventing/treating fever, dryness of eye, corneal epithelialdetachment, keratitis, corneal ulceration, conjunctival inflammation,dysfunction of masticatory, dysphagia, taste disorder, mouth odor, mouthdiscomfort, mouth infection, mouth inflammation, cardiovascularfunctional disorder, acute respiratory distress syndrome, peptic ulcersuch as gastric ulceration and duodenal ulcer, gastric inflammation,visceral pain, diarrhea, enteritis such as ulcerative colitis, kidneydisorder such as nephritis, pancreatitis, ulcer tissue, bone resorption,dysmenorrhea, premature labor, nephrosis, or symptom of low bloodpressure, comprising administrating an effective amount of a compoundrepresented by the general formula (1) of the above, salt thereof, orsolvate thereof, and pharmaceutically acceptable carrier to a patientsusceptible to or suffering from the forementioned conditions.

The present invention further relates to the use of the compound (1) ofthe present invention, salt thereof or solvate thereof for producing apharmaceutical composition for preventing/treating conditions associatedwith PAR-2.

The present invention further relates to the use of the compound (1) ofthe present invention, salt thereof or solvate thereof for producing apharmaceutical composition for preventing/treating fever, dryness ofeye, corneal epithelial detachment, keratitis, corneal ulceration,conjunctival inflammation, dysfunction of masticatory, dysphagia, tastedisorder, mouth odor, mouth discomfort, mouth infection, mouthinflammation, cardiovascular functional disorder, acute respiratorydistress syndrome, peptic ulcer such as gastric ulceration and duodenalulcer, gastric inflammation, visceral pain, diarrhea, enteritis such asulcerative colitis, kidney disorder such as nephritis, pancreatitis,ulcer tissue, bone resorption, dysmenorrhea, premature labor, nephrosis,or symptom of low blood pressure.

According to the present invention, PAR-2 agonist which can be aneffective agent for preventing/treating various conditions associatedwith PAR-2 can be provided. Consequently, the present invention relatesto the use of the compound represented by the compound (1) of thepresent invention, salt thereof or solvate thereof as PAR-2 agonist.

The present invention further relates to the use of the compoundrepresented by the compound (1) of the present invention, salt thereofor solvate thereof as an active ingredient in a pharmaceuticalcomposition for preventing/treating fever, dryness of eye, cornealepithelial detachment, keratitis, corneal ulceration, conjunctivalinflammation, dysfunction of masticatory, dysphagia, taste disorder,mouth odor, mouth discomfort, mouth infection, mouth inflammation,cardiovascular functional disorder, acute respiratory distress syndrome,peptic ulcer such as gastric ulceration and duodenal ulcer, gastricinflammation, visceral pain, diarrhea, enteritis such as ulcerativecolitis, kidney disorder such as nephritis, pancreatitis, ulcer tissue,bone resorption, dysmenorrhea, premature labor, nephrosis, or symptom oflow blood pressure.

BEST MODE FOR CARRYING OUT THE INVENTION

A_(r) in the general formula (1) represents a phenyl group or anaromatic heterocyclic group optionally having substituent(s), preferablyan aromatic heterocyclic group optionally having substituent(s). Thearomatic heterocyclic group of the present invention is a monocyclic,polycyclic or condensed cyclic group comprising 5- to 7-memberedaromatic heterocyclic ring wherein the aromatic heterocyclic ring hasone or more than two heteroatom(s) selected from a group consisting ofnitrogen, oxygen or sulfur within at least one ring. The preferablearomatic heterocyclic group is, for example, furyl group, pyridyl group,benzofuryl group, isoxazoryl group, or imidazolyl group, particularlyfuryl group.

The phenyl group and aromatic heterocyclic group mentioned above can bewith/without substituent(s). Examples of the substituent (s) are astraight chain or branched alkyl group having 1 to 8 carbon atoms,preferably 1 to 6, more preferably 1 to 3 carbon atoms, such as a methylgroup, ethyl group or n-propyl group; an alkoxy group composed of astraight chain or branched alkyl group having 1 to 8 carbon atoms,preferably 1 to 6, more preferably 1 to 3 carbon atoms, such as amethoxy group or ethoxy group; a halogen atom such as a bromine atom andchlorine atom. Examples of preferable substituted aromatic heterocyclicgroups are a bromofuryl group, dimethylfuryl group, etc.

-AA₁-AA₂-AA₃-AA₄- of the general formula (1) represents a peptidecomposed of 4 amino acids by notation for peptides, wherein the left endrepresents N-terminal and the right end represents C-terminal. EachAA₁-AA₂-AA₃, and AA₄ shows amino acids composing the peptide composed of4 amino acids.

A hydrophobic amino acid, an amino acid absent of substituent (s)comprising more than two carbon atoms, and a basic amino acid of thepresent invention can be an α-amino acid whose carboxyl group has aminogroup attached at the α position, and can be either natural orunnatural. When such amino acids are optically active, they can beD-isomer, L-isomer or racemate, however L-amino acid is usuallypreferred.

The amino acid represented by AA₁ is a hydrophobic amino acid, which is,for example, an α amino acid substituted with a saturated or unsaturatedstraight chain, branched or cyclic hydrocarbon group having 2 to 20carbon atoms, preferably 2 to 10, more preferably 3 to 10 carbon atoms,at the α position. Examples of the hydrocarbon group are straight-chainor branched alkyl group having 2 to 8 carbon atoms, preferably 2 to 6,more preferably 3 to 6 carbon atoms, such as isopropyl group,2-methylpropyl group and 1-methyl-propyl group; saturated cycloaliphatichydrocarbon group having 5 to 20 carbon atoms, preferably 5 to 10, morepreferably 6 to 10 carbon atoms, such as cyclohexylmethyl group andcyclohexylethyl group; or aromatic alphatic group (aralkyl group) having7 to 20 carbon atoms, preferably 7 to 12, more preferably 7 to 10 carbonatoms, such as benzyl group. Examples of preferable amino acid of AA₁are β-cyclohexylalanine, phenylalanine, isoleucine, luecine, valine,more preferably β-cyclohexylalanine.

AA₂ represents an amino acid absent of substituent(s) having more thantwo carbon atoms, preferably an amino acid absent of substituent(s)comprising more than one carbon atom. That is, AA₂ represents an aminoacid whose carbon chain between the carboxyl group and the amino groupis absent of substituent (s), or an amino acid having one or morehydrogen atom substituted with substituent(s) composing 0 or 1 carbonatom. Examples of a substituent comprising one carbon atom are methylgroup, chloromethyl group, fluoromethyl group, difluoromethyl group andtrifluoromethyl group, and a substituent composing 0 carbon atom is, forexample, halogen atoms such as chlorine atom and fluorine atom. Examplesof preferable amino acid for AA₂ are glycine such as glycine,α-fluoroglycine or α,α-difluoroglycine, and glycine derivatives such ashalogenated glycines; however, glycine is more preferable.

AA₃ represents an amino acid absent of substituent(s) having more thantwo carbon atoms, preferably an amino acid absent of substituent(s)comprising more than one carbon atom. That is, AA₂ represents an aminoacid whose carbon chain between the carboxyl group and the amino groupis absent of substituent(s), or an amino acid having one or morehydrogen atom substituted with substituent(s) composing 0 or 1 carbonatom. Examples of a substituent comprising one carbon atom are methylgroup, chloromethyl group, fluoromethyl group, difluoromethyl group andtrifluoromethyl group, and a substituent composing 0 carbon atom is, forexample, halogen atoms such as chlorine atom and fluorine atom. Examplesof preferable amino acid for AA₃ are glycine such as glycine,α-fluoroglycine or α,α-difluoroglycine, and glycine derivatives such ashalogenated glycines; however, glycine is more preferable.

The basic amino acid represented by AA₄ refers to an amino acid which issubstituted with one or two straight chain or branched saturated orunsaturated aliphatic hydrocarbon group having 1 to 10 carbon atoms,preferably 1 to 6 carbon atoms, having one or more than two basicsubstituent(s) such as amino group, substituted amino group, amidinogroup, guanidino group, cyclic amino group. The basic substituent groupherein is, for example, amino group; monoalkylamino group such as methylamino group and ethylamino group; dialkylamino group such asdimethylamino group and diethylamino group; cyclic amino group such aspyrrolidinyl group, piperidinyl group, morpholino group, piperazynylgroup, alkylpiperazynyl group, homopiperazynyl group,alkylhomopiperazynyl group, pyridyl group, imidazolyl group andalkylimidazolyl group; amidino group, guadinino group and the like.Alkyl group as a substituent in monoalkylamino group, dialkylaminogroup, alkylpiperazynyl group, alkylhomopiperazynyl group, oralkylimidazolyl group is, for example, alkyl group with 1 to 10 carbonatoms selected from a group consisting of straight chain or branchedalkyl group having 1 to 10, preferably 1 to 6 carbon atoms, andsaturated cyclo alkyl group (cyclo alkyl group) having 3 to 10,preferably 3 to 6 carbon atoms. Preferable alkyl group are, for example,methyl group, ethyl group, n-propyl group, n-butyl group, n-pentylgroup, n-hexyl group, isopropyl group, isobutyl group, sec-butyl group,cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexylgroup. Also, a straight chain or branched saturated or unsaturatedaliphatic hydrocarbon group with 1 to 10, preferably 1 to 6 carbon atomsis, for example, alkyl group or alkenyl group, preferably methyl group,ethyl group, and alkyl group such as n-propyl group, n-butyl group,n-pentyl group and n-hexyl group. Examples of preferable basic aminoacid are a amino acid substituted with methyl group, ethyl group,n-propyl group, n-butyl group, n-pentyl group and n-hexyl group havingpiperidinyl group at the α position, particularly a amino acidsubstituted with n-propyl group having piperidinyl group at the αposition is preferable, and α-[3-1(1-piperidinyl)propyl]glycine is themost preferable.

X shown in the general formula (1) is, for example, a straight chain orbranched bivalent saturated aliphatic hydrocarbon group having 1 to 6carbon atoms, preferably 1 to 4, more preferably 1 to 3 carbon atoms,and preferably a straight-chain group represented by the followingformula:

—(CH₂)_(n)—

wherein, n represents a whole number 1 to 6.

The bivalent saturated aliphatic hydrocarbon group is, for example,methylene group, ethylene group, propylene group, butylene group.Examples of preferable bivalent saturated aliphatic hydrocarbon groupare methylene group and ethylene group.

Y shown in the general formula (1) represents basic substituent(s);straight, branched, or cyclic bivalent saturated aliphatic hydrocarbongroup having 1 to 6 carbon atoms, or aromatic hydrocarbon having 6 to 10carbon atoms. The basic substituent means the basic substituent asdescribed above, which is amino group, monoalkylamino group,dialkylamino group, pyrrolidinyl group, piperidinyl group, morpholinogroup, piperazynyl group, alkylpiperazynyl group, homopiperazynyl group,alkylhomopiperazynyl group, pyridyl group, imidazolyl group,alkylimidazolyl group, amidino group, guadinino group and the like,preferably dialkylamino group, pyrrolidinyl group, piperidinyl group,morpholino group, alkylpiperazynyl group, alkylhomopiperazynyl group,pyridyl group. For alkyl group in monoalkylamino group, dialkylaminogroup, alkylpiperazynyl group, alkylhomopiperazynyl group, oralkylimidazolyl group herein is, for example, an alkyl group having 1 to10 carbon atoms selected from a group consisting of straight chain orbranched alkyl group having 1 to 10, preferably 1 to 6 carbon atoms, andsaturated cyclo alkyl group (cyclo alkyl group) having 3 to 10,preferably 3 to 6 carbon atoms; and the preferable alkyl group is, forexample, methyl group, ethyl group, n-propyl group, n-butyl group,n-pentyl group, n-hexyl group, isopropyl group, isobutyl group,sec-butyl group, cyclopropyl group, cyclobutyl group, cyclopentyl group,cyclohexyl group.

A straight, branched, or cyclic bivalent saturated aliphatic hydrocarbongroup having 1 to 6 carbon atoms represented by Y is hydrocarbon groupselected from a group consisting of straight chain or branched alkylgroup having 1 to 6 carbon atoms, for example, methyl group, ethylgroup, n-propyl group, n-butyl group, n-pentyl group, n-hexyl group,isopropyl group, isobutyl group, sec-butyl group, cyclopropyl group,cyclobutyl group, cyclopentyl group, cyclohexyl group, preferablycyclopentyl group and cyclohexyl group.

Also, an aromatic hydrocarbon group having 6 to 10 carbon atomsrepresented by Y is monocyclic, polycyclic, or condensed-cyclichydrocarbon group having at least one of 6-membered aromatic ring; forexample, phenyl group, indenyl group, naphthyl group and tetrahydronaphthyl group, and preferable aromatichydrocarbon group is, forexample, phenyl group or naphthyl group. Examples of particularlypreferable group are Piperidinyl group and phenyl group.

A salt of the compound represented by the general formula (1) is, butnot limited to insofar as pharmaceutically acceptable salt, preferablyan acid addition salt, for example, mineral acid addition salt such ashydrochloride, hydrobromide, hydroiodide, sulfate and phosphate; andorganic acid addition salt such as benzoate, methanesulfonate,ethanesulfonate, benzenesulfonate, p-toluenesulfonate, oxalate, maleate,fumarate, tartrate, citrate and acetate.

Further, when the compound represented by the general formula (1) is inthe form of solvate such as hydrate, the solvate can be comprised in thecompound. Further, when the compound represented by the general formula(1) has one or more of asymmetric carbon atoms, the present inventionalso includes any configurational isomers.

The PAR-2 activation of peptide derivatives represented by the generalformula (1) can be tested by various known methods. For example, themethod of Hollenberg (Hollenberg, M. D., et al., Can. J. Physiol.Pharmacol., 75, 832-841 (1997)), the method of Kawabata et al.(Kawabata, A., et al., J. Pharmacol. Exp. Ther., 288, 358-370 (1999)),the method of Howthorne et al. (Howthorne et al., A High-ThroughputMicrotiter Plate-Based Calcium Assay for the Study of Protease-ActivatedReceptor 2 Activation, Analytical Biochemistry 290, 378-379 (2001)), andthe like can be used. The present inventors tested PAR-2 activationpotency by using the modified method of Howthorne et al. Morespecifically the method is for assaying calcium dynamics in a cellexpressing human PAR-2 intracellularly. In this assay, PAR-2 agonistmediated calcium dynamics (concentration variability) in a cell ismeasured by using a multiple-well plate reader wherein the cell has Ca²⁺sensitive fluorescent dye introduced and stimulated by PAR-2 agonistunder probenecid, which inhibits anion-exchange transporter, present.

The method is described below in more detail.

HCT-15 cells, human colorectal cancer cell lines endogenously expressinghigh level of PAR-2, were plated in a black-wall clear-bottom 96 wellplate. Subconfluent cells were labeled with Ca²⁺ sensitive fluorescentdye (Calcium Assay Reagent, Molecular Devices) in a RPMI culture mediumin the presence of 2.5 mM probenecid absence of serum, and incubated for1 hour at 37° C. Thereafter, the cells were stimulated with testcompounds at various concentrations, and fluorescence change wasmeasured using a scanning fluorometer (Flex Station, Molecular Devices)using excitation wavelength of 485 nm and fluorescence wavelength of 525nm (cut-off wavelength of 515 nm). As a comparative compound, SLIGKV-OHwhich is known as PAR-2 activated peptide was used. The results areshown in FIG. 1.

[FIG. 1] Compound MW Agonist activity (Example No.) (Calculated value)(EC50, μM) Comparison compound — 15.6 ± 0.9  (SLIGKV—OH) Example 1650.81 2.3 ± 0.3 Example 2 744.79 4.1 ± 0.4

As a result, both compounds of example 1 and example 2 showed higheragonist activity against PAR-2.

A compound represented by the general formula (1) below can besynthesized by forming five amide-linkages by amidation between anappropriate carboxylic acid and an appropriate amine in a molecule inarbitrary order. It is possible to introduce an amide-linkage at theN-terminus and C-terminus after producing peptide portion according to aconventional method of peptide synthesis; however, in an example ofpreferable method for producing the composition, a peptide -AA₂-AA₃- issynthesized initially, then -AA₁- is bound to the dipeptide -AA₂-AA₃-here the peptide H-AA₁-AA₂-AA₃-OH is protected in need. The group at theN-terminus is acylated to provide N-acylated peptide represented by ageneral formula (2):

Ar—CO-AA¹-AA²-AA³-OH  (2)

wherein,A_(r), AA₁, AA₂, and AA₃ represent the same as the above-mentioned. TheN-acylated peptide is then reacted with amino acid derivativesrepresented by a general formula (3):

H-AA₄-NH—X—Y  (3)

wherein,AA₄ and R₁ represent the same as the above-mentioned, to obtain acompound represented by the general formula (1). Amino acid derivativesrepresented by the general formula (3) above can be produced preferablyby reacting AA₄ whose amino group is protected and amine of NH₂—R₁.

For such an N-acylation reaction and an amidation reaction, variousamidation methods used for conventional peptide synthesis areapplicable. Various methods such as solid-phase methods andsolution-phase methods can also be used.

For amidation in the present invention, a method of peptide synthesissuch as activated ester method and anhydride method can be usedarbitrarily, preferably a method using a condensation reagent and amethod using a reactive derivative of the compound having a carboxylgroup. Examples of the condensation reagent in the amidation are1,3-dicyclohexylcarbodiimide,1-cyclohexyl-3-morpholinoethylcarbodiimide,1-(3-diaminopropyl)-3-ethylcarbodiimide, 1,1′-carbonyldiimidazole,diethylphosphorocyanidate, diphenylphosphoryl azide,bis(2-oxo-3-oxazolydinyl)phosphonic chloride,2-chloro-1-methylpyridinium iodide, and the like. Examples of thereactive derivatives of the compound having a carboxyl group are an acylhalide such as acid chloride, acid azide, symmetric anhydride, or mixedanhydride formed with, for example, pivalic acid, an activated estersuch as p-nitrophenyl ester and the like. If necessary, an appropriatebase or appropriate solvent can be used when these reactions are carriedout. Examples of the bases are an organic bases such as pyridine,triethylamine, and N,N-diisopropylethylamine; or an inorganic base suchas sodium carbonate, and sodium hydrogencarbonate. Examples of thesolvent are such as N,N-dimethylformamide, tetrahydrofuran, 1,4-dioxane,acetonitrile, methylene chloride, and 1,2-dichroloethane. Further, whena condensation reagent such as 1,3-dicyclohexylcarbodiimide is used, itis effective to add an appropriate activating agent such as1-hydroxybenzotriazole and N-hydroxysuccinimide to accelerate thereaction and to inhibit racemization. Further, to simplify an isolationoperation of the synthesized peptide, various reagents listed here canbe modified for a solid-phase by binding on a resin such as polystyrene.

In the process of synthesizing the compound represented by the generalformula (1), functional groups present in starting materials andintermediates that should not engage with the expected reaction, can beprotected and deprotected in order to inhibit unfavourable sidereactions. For the protection and deprotection, a conventional method ofpeptide synthesis can be applied. For example, as the protected carboxylgroup, methyl ester, ethyl ester, t-butyl ester, and benzyl ester can beused; and as the protected amino group, methyl carbamate, allylcarbamate, t-butyl carbamate, benzyl carbamate, 9-fluorenylmethylcarbamate, p-methoxybenzyl carbamate, a formamide, acetamide,3-nitro-2-pyridinesulfenamide, phthalimide can be used. These protectinggroups can be removed by acid treatment, base treatment, reduction,hydrolysis and the like according to the properties of the protectinggroups. The acid used in these methods is hydrogen chloride, hydrogenfluoride, methanesulfonic acid, trifluoromethanesulfonic acid,trifluoroacetic acid, trimethylsilyl bromide, trimethylsilyltriflucromethanesulfonate, tetrafuloroboric acid, boron tribromide andthe like; and the base is piperidine, pyrrolidine, triethylamine,N,N-diisopropylethylamine and the like. Further, for reductivecondition, sodium/liquid ammonia, palladium catalyst/hydrogen, palladiumcatalyst/formic acid and the like can be used; and for hydrolysiscondition, lithium hydroxide, sodium hydroxide and the like can be used.

The compound relating to the present invention obtained by the abovemethod can be purified in need by the usual method, for example, gelchromatography, partition chromatography, ion-exchange chromatography,affinity chromatography, countercurrent chromatography, high-performanceliquid chromatography with various absorbents, or recrystallization andthe like. The compound can also be obtained in the form of a salt orsolvate expected as above according to the usual manner. The morespecific examples of the method producing the compound represented bythe general formula (1) are described in more detail with reference tothe Examples.

The pharmaceutical composition of the present invention contains thecompound represented by the general formula (1), salt thereof andsolvate thereof as the active ingredient, and the administration routeincludes, but not limited to, for example an oral agent, an injection, asuppository, an ointment, an inhalant, eye drops, nasal drops, and anadhesive preparation, and any of these can be selected according to thetherapeutic purpose. A pharmaceutical composition suitable for eachadministration route comprise a pharmaceutically acceptable carrier andcan be manufactured according to a method known to those skilled in theart.

In preparing an oral solid preparation, add excipients; and a binder, adisintegrating agent, a lubricant, a coloring agent, a flavoringsubstance, a fragrant substance and the like in need, to the compoundrepresented by the general formula (1) of the present invention, andthen produce tablets, coated tablets, granules, powder, capsules or thelike in a usual manner. Such additives may be those generally used inthe art; for example, the excipients include lactose, sucrose, sodiumchloride, glucose, starch, calcium carbonate, kaolin, microcrystallinecellulose, silicic acid and the like, the binder includes water,ethanol, propanol, simple syrup, glucose solution, starch solution,gelatin solution, carboxymethyl cellulose, hydroxypropyl cellulose,hydroxypropyl starch, methyl cellulose, ethyl cellulose, shellac,calcium phosphate, polyvinylpyrrolidone and the like; the disintegratingagent includes dry starch, sodium alginate, powdered agar, sodiumhydrogen carbonate, calcium carbonate, sodium lauryl sulfate,monoglyceride stearate, lactose and the like, the lubricant includespurified talc, stearate, borax, polyethylene glycol and the like; andthe flavoring substance includes sucrose, wild orange peel, citric acid,tartaric acid and the like.

In preparing an oral liquid preparation, add a flavoring substance, abuffer agent, a stabilizer, a fragrant substance and the like to thecompound represented by the general formula (1), to produce an oralliquid for internal use, syrup, elixir and the like in a usual manner.Here the flavoring substance may be the one described above; the bufferagent includes sodium citrate and the like; and the stabilizer includestragacanth, gum arabic, gelatin and the like.

In preparing an injection, add pH adjusting agent, a buffer agent, astabilizer, a tonicity agent, a topical anesthetic agent or the like tothe compound represented by the general formula (1), to producesubcutaneous, intramuscular and intravascular injections in a usualmanner. Here the pH adjusting agent and the buffer agent include sodiumcitrate, sodium acetate, sodium phosphate and the like. The stabilizerincludes sodium pyrosulfite, EDTA, thioglycolic acid, thiolactic acidand the like. The topical anesthetic agent includes procainehydrochloride, lidocaine hydrochloride and the like. The tonicity agentcan be exemplified by sodium chloride, glucose and the like.

In preparing a suppository, add pharmaceutical carriers known in theart, such as polyethylene glycol, lanolin, cacao seed oil, fatty acidtriglyceride and the like, and add a surfactant such as Tween® in need,and then produce a suppository in a usual manner.

In preparing an ointment, add additives usually used such as a base, astabilizer, a moistening agent and a preservative to the compoundrepresented by the general formula (1) in need, blend them in a usualmanner to produce an ointment. The base includes liquid paraffin, whitepetrolatum, Sarashi beeswax, octyldodecyl alcohol, paraffin and thelike. The preservative includes methyl p-hydroxybenzoate, ethylp-hydroxybenzoate, propyl p-hydroxybenzoate, and the like.

In addition to those described above, an inhalant, eye drops and nasaldrops can also be prepared in a usual manner.

The amount of the active ingredient in the pharmaceutical composition ofthe present invention to be administered varies depending on such as theage, sex, weight and symptoms of the patient, therapeutic effect,treatment time, administration form, and administration frequency, butusually the compound (1) of the present invention is administered to anadult orally or parenterally in the range of 0.001 to 1000 mg,preferably 0.01 mg to 500 mg, more preferably 0.1 mg to 100 mg all atonce or in divided portions per day. However, the dose varies dependingon various conditions, and thus a dose lower than the above may besufficient in some cases or a dose higher than the above range may benecessary in other cases. For example, the injection can be produced bydissolving or suspending the compound represented by the general formula(1) of the present invention at a concentration of 0.1 μg/mL to 10 mg/mLin a nontoxic pharmaceutically acceptable carrier such as physiologicalsaline or commercial distilled water for injection.

The injection thus obtained can be administered in a dose of 1 μg to 100mg, preferably 50 μg to 50 mg, for each administration, per body kg onceto several times per day to a patient in need of treatment. Theadministration route can be exemplified by medically suitableadministration route such as intravenous injection, subcutaneousinjection, intradermal injection, intramuscular injection andintraperitoneal injection, preferably intravenous injection. Theinjection can also be prepared as a suspension or emulsion with anon-aqueous diluent (for example, propylene glycol, polyethylene glycoland vegetable oils such as olive oil and alcohols such as ethanol)depending on the case. Sterilization of such injections can be carriedout by filter sterilization, that is, through a bacteria-retainingfilter, or with a sterilizer or through γ-ray irradiation. The injectioncan be produced in a form for preparation just before use. That is, agerm-free solid composition is produced by lyophilization and can bedissolved in germ-free distilled water for injection or other solventjust before use.

The thus obtained compound represented by the general formula (1) of thepresent invention has PAR-2 agonist action as shown later in the TestExamples; therefore, the compound can be used as PAR-2 agonist. Further,the compound is useful for prevention of development or progress,amelioration, and treatment of PAR-2 associated conditions, for example,fever, dryness of eye, corneal epithelial detachment, keratitis, cornealulceration, conjunctival inflammation, dysfunction of masticatory,dysphagia, taste disorder, mouth odor, mouth discomfort, mouthinfection, mouth inflammation, cardiovascular functional disorder, acuterespiratory distress syndrome, peptic ulcer such as gastric ulcerationand duodenal ulcer, gastric inflammation, visceral pain, diarrhea,enteritis such as ulcerative colitis, kidney disorder such as nephritis,pancreatitis, ulcer tissue, bone resorption, dysmenorrhea, prematurelabor, nephrosis, or symptom of low blood pressure.

Further, the compound represented by the general formula (1) is alsouseful for prevention of development or progress, amelioration, andtreatment of fever (rheumatic fever and influenza and other viralinfection-related fever), common cold, dysmenorrheal, menstrual cramp,Crohn's disease, emphysema, acute respiratory distress syndrome,transplant toxic potency, dyscrasia, tissue ulcer, peptic ulcer,gastritis, diverticulitis, recurrent gastrointestinal lesion,gastrointestinal bleeding, blood coagulation, anemia, gout, ankylosingspondylitis, restenosis, periodontal disease, skin fragility,osteoporosis, prosthesis implant loosening, aortic aneurysm(abdominalaortic aneurysm and cerebral aortic aneurysm), periarteritis nodosa,congestive heart failure, spasm, head injury, spinal cord injury,neurogenerative disease (acute neurogenerating disease and chronicneurogenerating disease), Huntington's disease, Parkinson's disease,migraine headache, depression, peripheral neuropathy, gingivitis,cerebral amyloid angiopathy, nootropic or recognition enhancement,amyotrophic lateral sclerosis, multiple sclerosis, corneal injury,yellow spot degeneration, tendinitis, myasthenia gravis, polymyositis,myositis, bursitis, burn, diabetes mellitus(types I and type II diabetesmellitus, diabetic retinopathy), tumor invasion, tumor growth, tumormetastasis, corneal scar, scleritis, immunodeficiency disorders (forexample, human AIDS and feline AIDS), sepsis, preterm delivery,hypoprothrombinemia, hemophila, thyroidititis, sarcoidosis, Bechet'ssyndrome, anaphylaxis kidney disorders and the like.

EXAMPLES

Hereinafter, the present invention is described in more detail byreference to the Examples, but the technical scope of the presentinvention is not limited to the Examples.

Reference Example 1 Production of2-furoyl-β-cyclohexyl-L-alanyl-glycyl-glycine

2-furoyl-β-cyclohexyl-L-alanyl-glycyl-glycine represented by theformula:

is produced according to the following method.

To a solution of 289.4 mg (1.47 mmol) of glycyl-glycine ethyl esterhydrochloride in anhydrous tetrahydrofuran (5 mL), 155.9 mg (1.54 mmol)of triethylamine, 451.5 mg (1.47 mmol) ofN-t-butoxycarbonyl-β-cyclohexyl-L-alanine dihydrate, 205.3 mg (1.52mmol) of 1-hydroxybenzotriazole hydrate, and 292.7 mg (1.53 mmol) of1-[3-(dimethylaminomethyl)propyl]-3-ethylcarbodiimide hydrochloride wereadded sequentially with stirring under ice cooling. After the mixturewas stirred for 1 hour, the reaction mixture was stirred at roomtemperature for 0.5 hour. The reaction mixture was concentrated underreduced pressure, chloroform (30 ml) was added to the residues, and thesolution was washed sequentially with 0.5M hydrochloric acid (3×5 mL),water (3×5 mL) and 5% aqueous sodium hydrogen carbonate solution (3×5mL). The organic layer was dried over anhydrous sodium sulfate andconcentrated under reduced pressure, whereby 570 mg of a crude productwas obtained. The crude product was purified by column chromatography onalumina (alumina 2 g, chloroform), to give 552.8 mg ofN-t-butoxycarbonyl-β-cyclohexyl-L-alanyl-glycyl-glycine ethyl ester(yield 91%) as a colorless crystalline powder.

To the resulting solution ofN-t-butoxycarbonyl-β-cyclohexyl-L-alanyl-glycyl-glycine ethy lester(506.2 mg, 1.22 mmol) in acetic ether (1 mL) under ice-cold condition,add 4M hydrogen chloride/acetic ether (3.0 mL, 12 mmol) with stirring,and then stir the reaction mixture for 4.5 hours at room temperature.Add diethylether (12 mL) and stir the mixture under ice-cold condition,filtrate and correct the precipitate to obtain hygroscopic crudecrystals. Suspend the crude crystals in diethylether (10 mL), filtrateand collect to obtain β-cyclohexyl-L-alanyl-glycyl-glycine ethyl esterhydrochloride (370.3 mg) as colorless crystalline powder (yield 86%).

To a solution of β-cyclohexyl-L-alanyl-glycyl-glycine ethyl esterhydrochloride (90.1 mg, 0.258 mmol) in methylenechloride (1 mL), addN,N-diisopropylethylamine (100.0 mg, 0.774 mmol) and 2-furoyl chloride(37.2 mg, 0.285 mmol) with stirring. Stir the reaction mixture for 0.5hour. Add methanol (0.2 mL), stir the reaction mixture under roomtemperature, concentrate under vacuum. To the residue, add chloroform(25 mL), wash the solution with 0.5 M hydrochloric acid (3×5 mL) and 5%aqueous sodium hydrogencarbonate solution (3×5 mL). Dry the organicphase over anhydrous sodium sulfate, and concentrate under vacuum toobtain crude product (127 mg). Purify the resulting crude product bysilica-gel column chromatography [silica-gel 7.5 g,chloroform/methanol-chloroform (1:100)] to obtain2-furoyl-β-cyclohexyl-L-alanyl-glycyl-glycine ethyl ester (103.2 mg) asa colorless oily matter (yield 98%).

To the resulting 2-furoyl-β-cyclohexyl-L-alanyl-glycyl-glycine ethylester (22.5 mg, 0.0552 mmol) in tetrahydrofuran (0.2 mL), add water (0.1mL) and lithium hydroxide hydrate (2.7 mg, 0.0643 mmol). Stir themixture for 1 hour at room temperature, add water-ethanol (1:10, 0.5 mL)and weakly acidic ion-exchange resin (Amber-lite™ IRC-50H⁺) (48.1 mg;about 0.48 mg equivalent), and stir the mixture for 0.5 hour. SwellIRC-50 (0.3 mg) in water-ethanol (1:10), fill a glass tube, load themixture on, then elute the column with water-ethanol (1:10, 7.5 mL).Concentrate the eluate under vacuum to obtain the title compound (20.3mg) as colorless oily matter.

Reference Example 2 Production of (S)-2-amino-5-(1-piperidinyl)pentanoicacid benzyl amide

(S)-2-amino-5-(1-piperidinyl)pentanoic acid benzyl amide represented bythe formula:

is produced according to the following method.

To a solution of N-t-butoxycarbonyl-(S)-2-amino-5-iodinated pentanoicacid benzyl ester (J. Org. Chem. 1998, 7875-7884)(100.8 mg, 0.23 mM) inN,N-dimethylformamide (0.25 mL), add piperidine (41.5 mg, 0.49 mmol).Stir the mixture for 3 hours at room temperature, and then addchloroform (30 mL). Wash the mixture with saturated sodium hydrogencarbonate solution (3×3 mL). Dry the organic phase over anhydrous sodiumsulfate, and concentrate under vacuum to obtain crudeN-t-butoxycarbonyl-(S)-2-amino-5-(1-piperidinyl)pentanoic acid benzylester (83.8 mg) as colorless oily matter.

To a solution of crudeN-t-butoxycarbonyl-(S)-2-amino-5-(1-piperidinyl)pentanoic acid benzylester in ethanol (1.5 mL), add 5% palladium-carbon (15.0 mg). Stir themixture for 1 hour under hydrogen atmosphere. Remove the insolublematter by vacuum filtration using sellite, and wash the residue withethanol (10 mL). Mix the filtrate and wash liquid, and concentrate undervacuum to obtain crudeN-t-butoxycarbonyl-(S)-2-amino-5-(1-piperidinyl)pentanoic acid (69.0 mg)as colorless oily matter.

To a solution of crudeN-t-butoxycarbonyl-(S)-2-amino-5-(1-piperidinyl)pentanoic acid (22.2 mg,0.074 mmol) in unhydrous methylene chloride (0.50 mL), add benzyl amine(9.7 mg, 0.091 mmol) and 1-hydroxybenzotriazol monohydrate (11.1 mg,0.082 mmol). Stir the reaction mixture under ice-cold condition, and add1,3-dicyclohexylcarbodiimide (18.0 mg, 0.087 mmol), and then stir for0.5 hour. Remove the ice bath, stir for 16 hours at room temperature,and then add chloroform (20 mL). Wash the organic phase with saturatedsodium hydrogen carbonate solution (2×3 mL), dry over anhydrous sodiumsulfate, and concentrate under vacuum to obtain crude oily matter (47.7mg). Purify by column chromatography (silica gel 2 g, about 15%ammonia/methanol-chloroform (1:100)) to obtainN-t-butoxycarbonyl-(S)-2-amino-5-(1-piperidinyl)pentanoic acid benzylamide (26.2 mg) as colorless oily matter [yield 90% fromN-t-butoxycarbonyl-(S)-2-amino-5-(1-piperidinyl)pentanoic acid benzylether].

To a solution ofN-t-butoxycarbonyl-(S)-2-amino-5-(1-piperidinyl)pentanoic acid benzylamide (26.2 mg, 0.067 mmol) in acetic ether (0.5 mL), add 4M hydrogenchloride/ethyl acetate solution (1.0 mL, 4 mmol), and stir the reactionmixture for 2 hours at room temperature. Concentrate the reactionmixture under vacuum, purify the residue by alumina columnchromatography [alumina 0.3 g, methanol-chloroform (1:4)] to obtain thetitle compound as colorless oily matter (yield 68%)

Example 1 Production of(S)-2-[2-furoyl]-β-cyclohexylamine-L-aranyl-glycine-glycyl-amino]-5-(1-piperidinyl)pentanoicacid benzyl amide

The title compound represented by the formula:

is produced according to the following method.

To a solution of the 2-furoyl-β-cyclohexyl-L-alanyl-glycyl-glycine (21.4mg, 0.056 mmol) produced according to Reference Example 1 descrivedabove, and (S)-2-amino-5-(1-piperidinyl)-pentanoic acid benzyl amideproduced according to Reference Example 2 (13.2 mg, 0.046 mmol) inanhydrous methylene chloride (0.5 mL), add 1-hydroxy benzotriazolemonohydrate with stirring under ice-cold conditions. Stir the mixturefor 1 hour under ice-cold condition, stir for 12 hours at roomtemperature, and then purify the reaction mixture by Sillica-GelThin-Layer Chromatography [about 15% ammonia/methanol-chloroform (1:10)]to obtain colorless oily matter (33.8 mg). Purify the oily matter bySillica-Gel Thin-Layer Chromatography [about 15%ammonia/methanol-chloroform-toluene (1:3:3)] to obtain the titlecompound (27.8 mg) as colorless oily matter (yield 94%). Recrystallizecolorless oily matter of the title compound with chloroform-hexane toobtain colorless crystalline powder (melting point 205-209° C.).

¹H-NMR (CDCl₃) δ: 7.95 (1H, br. s), 7.86 (1H, br. s), 7.50-7.70 (2H, m)7.38 (1H, br. s), 7.20-7.30 (6H, m), 7.03 (1H, br. d, J=3.2 Hz), 6.42(1H, dd, J=3.2, 1.6 Hz), 4.58-4.75 (2H, m), 4.47 (1H, dd, J=15.0, 5.9Hz), 4.37 (1H, dd, J=15.0, 5.7 Hz), 3.91-4.12 (4H, m), 2.24-2.41 (6H,m), 1.45-2.00 (16H, m), 1.30-1.45 (2H, m), 1.06-1.29 (3H, m), 0.84-1.01(2H, m).

Example 2 Production of(S)-2-[2-furoyl]-β-cyclohexyl-L-alanyl-glycyl-glycyl-amino]-5-(1-piperidinyl)pentanoicacid-N-[2-(1-piperidinyl)ethyl]amide. Dihydrochlorides.

A compound represented by the formula:

is produced according to the following method.

2-furoyl-L-phenylaranyl-glycyl glycine (23.7 mg, 0.063 mmol) is obtainedin the same way as example 1, and(S)-2-[(2-furoyl)-β-cyclohexyl-L-alanyl-glycyl-glycyl-amino]-5-(1-piperidinyl)pentanoicacid[2-(1-piperidinyl)ethyl]amide (20.8 mg) is obtained from(S)-2-amino-5-(1-piperidinyl)pentanoicacid-N-[2-(1-piperidinyl)ethyl]amide (16.7 mg, 0.054 mmol) synthesizedin the same way as reference example 1, both as colorless oily matter(yield 58%). To a solution of(S)-2-[(2-furoyl)-β-cyclohexyl-L-alanyl-glycyl-glycyl-amino]-5-(1-piperidinyl)pentanoicacid[2-(1-piperidinyl)ethyl]amide (20.8 mg, 0.031 mmol) in ethanol (1.0mL), add 1.0 M hydrochloric acid (0.10 mL, 0.10 mmol) and concentratedunder vacuum. To the residue, add ethanol (5.0 mL) and concentratedunder vacuum. Then, recrystallize the residue withchloroform-diethylether to obtain the title compound as colorlesscrystalline powder (melting point 138° C.)

¹H-NMR (CDCl₃) δ: 11.14 (1H, br. s), 9.73 (1H, br. s), 8.49 (1H, br. s),8.17 (1H, br. s), 8.08 (1H, br. d, J=7.6 Hz), 7.97 (1H, br. s), 7.59(1H, br. d, J=7.6 Hz), 7.52 (1H, br. s), 7.21 (1H, br. d, J=3.4 Hz),6.50 (1H, dd, J=3.4, 1.8 Hz), 4.69-4.77 (1H, m), 4.40 (1H, br. ddd,J=6.8, 6.8, 6.8 Hz), 4.23 (1H, dd, J=16.7, 6.5 Hz), 4.13 (1H, dd,J=16.7, 7.2 Hz), 3.66-3.90 (5H, m), 3.44-3.64 (3H, m), 3.23 (2H, br. s),2.92-3.08 (2H, m), 2.58-2.77 (4H, m), 1.59-2.27 (21H, m), 1.32-1.52 (3H,m), 1.07-1.29 (3H, m), 0.87-1.04 (2H, m).

INDUSTRIAL APPLICABILITY

The present invention provides a useful compound having PAR-2 agonistaction as well as PAR-2 agonist which has improved ability of PAR-2activation compared to TRAP with reducing the number of amino acid. Thepresent invention also provides PAR-2 agonist useful for development ofa pharmaceutical preparation as well as prevention of development orprogress, amelioration, and treatment of conditions such as fever,dryness of eye, corneal epithelial detachment, keratitis, cornealulceration, conjunctival inflammation, dysfunction of masticatory,dysphagia, taste disorder, mouth odor, mouth discomfort, mouthinfection, mouth inflammation, cardiovascular functional disorder, acuterespiratory distress syndrome, peptic ulcer such as gastric ulcerationand duodenal ulcer, gastric inflammation, visceral pain, diarrhea,enteritis such as ulcerative colitis, kidney disorder such as nephritis,pancreatitis, ulcer tissue, bone resorption, dysmenorrhea, prematurelabor, nephrosis, or symptom of low blood pressure.

1. A compound represented by the general formula (1), salt thereof orsolvate thereof:Ar—CO-AA₁-AA₂-AA₃-AA₄-NH—X—Y  (1) Wherein, Ar represents a phenyl groupor an aromatic heterocyclic group optionally having substituent(s); AA₁represents a hydrophobic amino acid; AA₂ represents an amino acid absentof substituent(s) comprising more than two carbon atoms; AA₃ representsan amino acid absent of substituent(s) comprising more than two carbonatoms; AA₄ represents a hydrophobic amino acid; X represents a bivalentsaturated aliphatic hydrocarbon group with 1-6 carbon atoms; Yrepresents basic substituent(s); straight, branched, or cyclic bivalentsaturated aliphatic hydrocarbon group having 1 to 6 carbon atoms, oraromatic hydrocarbon having 6 to 10 carbon atoms.
 2. A compound, salt orsolavate according to claim 1 wherein, in the general formula (1), Ar isa monocyclic, polycyclic, or condenced cyclic aromatic heterocyclicgroup comprising 5-7 membered aromatic heterocyclic ring having one ortwo or more of heteroatom(s) selected from a group consisting ofnitrogen, oxygen and sulfur in at least one ring, and may havesubstituent(s) of straight chain or branched alkyl group having 1 to 8carbon atoms, alkoxy group comprised of straight chain or branched alkylgroup having 1 to 8 carbon atoms, or halogen atom: AA₁ is an amino acidβ-cyclohexylalanine, phenylalanine, isoleucine, luecine, or valine: AA₂and AA₃ are identically or independently amino acids; glycine,α-fluoroglycine or α,α-difluoroglycine: AA₄ is an α-amino acid which issubstituted at the α-position with straight chain or branched alkylgroup having 1 to 6 carbon atom(s) having one or more than two types ofbasic substituent(s) selected from amino group, monoalkylaminosubstituted with alkyl group having 1 to 10 carbon atom(s), dialkylaminogroup substituted with alkyl group having 1 to 10 carbon atom(s),pyrrolidinyl group, piperidinyl group, morpholino group, piperazynylgroup, alkylpiperazynyl group substituted with alkyl group having 1 to10 carbon atom(s), homopiperazynyl group, alkylhomopiperazynyl groupsubstituted with alkyl group having 1 to 10 carbon atom(s), pyridylgroup, imidazolyl group, alkylimidazolyl group substituted with alkylgroup having 1 to 10 carbon atom(s), amidino group and guadinino group:X is a straight chain-group represented by the formula:_13 (CH₂)_(n)— Wherein, n represents a whole number 1 to 6: Y is a groupselected from a group consisting of dialkylamino group substituted withalkyl group having 1 to 10 carbon atom(s), pyrrolidinyl group,piperidinyl group, morpholino group, piperazynyl group substituted withalkyl group having 1 to 10 carbon atom(s), alkylhomopiperazynyl groupsubstituted with alkyl group having 1 to 10 carbon atom(s), pyridylgroup, cyclopentyl group, cyclohexyl group, phenyl group and naphthylgroup.
 3. A compound, salt or solvate according to claim 2 wherein, inthe general formula (1), Ar is furyl group, pyridyl group, benzofurylgroup, isoxazoryl group, imidazolyl group, bromofuryl group, ordimethylfuryl group.
 4. A compound, salt or solvate according to claim 1wherein, in the general formula (1), A_(r) is furyl group: AA₁ isβ-cyclohexylalanine; AA₂ and AA₃ are glycine: AA₄ is an α-amino acidwhich is substituted at the α-position with methyl group havingpiperidinyl group, ethyl group, n-propyl group, n-butyl group, n-pentylgroup or n-hexyl group: X is methylene group or ethylene group: and Y ispiperidinyl group or phenyl group.
 5. A compound, salt or solvateaccording to claim 1 wherein a compound represented by the formula (1)is(S)-2-[2-furoyl]-β-cyclohexylamine-L-aranyl-glycyl-glycyl-amino]-5-(1-piperidinyl)pentanoicacid benzyl amide or(S)-2-[(2-furoyl)-β-cyclohexyl-L-alanyl-glycyl-glycyl-amino]-5-(1-piperidinyl)pentanoicacid[2-(1-piperidinyl)ethyl]amide.
 6. A pharmaceutical compositioncomprising a compound, salt or solvate according to claim 1 andpharmaceutically acceptable carrier.
 7. A pharmaceutical compositionaccording to claim 6 wherein, the pharmaceutical composition is forpreventing/treating conditions associated with PAR-2.
 8. Apharmaceutical composition according to claim 6 wherein, thepharmaceutical composition is for preventing/treating fever, dryness ofeye, corneal epithelial detachment, keratitis, corneal ulceration,conjunctival inflammation, dysfunction of masticatory, dysphagia, tastedisorder, mouth odor, mouth discomfort, mouth infection, mouthinflammation, cardiovascular functional disorder, acute respiratorydistress syndrome, peptic ulcer such as gastric ulceration and duodenalulcer, gastric inflammation, visceral pain, diarrhea, enteritis such asulcerative colitis, kidney disorder such as nephritis, pancreatitis,ulcer tissue, bone resorption, dysmenorrhea, premature labor, nephrosis,or symptom of low blood pressure.
 9. A method for preventing/treatingconditions associated with PAR-2, comprising administrating an effectiveamount of a compound, salt or solvate according to claim 1 to a patientsusceptible to or suffering from a condition associated with PAR-2. 10.A method for preventing/treating conditions according to claim 9wherein, the condition associated with PAR-2 is fever, dryness of eye,corneal epithelial detachment, keratitis, corneal ulceration,conjunctival inflammation, dysfunction of masticatory, dysphagia, tastedisorder, mouth odor, mouth discomfort, mouth infection, mouthinflammation, cardiovascular functional disorder, acute respiratorydistress syndrome, peptic ulcer such as gastric ulceration and duodenalulcer, gastric inflammation, visceral pain, diarrhea, enteritis such asulcerative colitis, kidney disorder such as nephritis, pancreatitis,ulcer tissue, bone resorption, dysmenorrhea, premature labor, nephrosis,or symptom of low blood pressure.
 11. Use of a compound, salt or solvateaccording to claim 1 for the manufacture of a pharmaceutical compositionfor preventing/treating conditions associated with PAR-2.
 12. Useaccording to claim 11, wherein the condition associated with PAR-2 isfever, dryness of eye, corneal epithelial detachment, keratitis, cornealulceration, conjunctival inflammation, dysfunction of masticatory,dysphagia, taste disorder, mouth odor, mouth discomfort, mouthinfection, mouth inflammation, cardiovascular functional disorder, acuterespiratory distress syndrome, peptic ulcer such as gastric ulcerationand duodenal ulcer, gastric inflammation, visceral pain, dirrhea,enteritis such as ulcerativecolitis, kidney disorder such as nephritis,pancreatitis, ulcer tissue, bone resorption, dysmenorrhea, prematurelabor, nephrosis, or symptom of low blood pressure.